This invention relates generally to transport refrigeration systems, and more particularly, to a shield arranged between a tractor and a trailer of a transport refrigeration system.
Refrigerated trucks, trailers, and intermodal containers, collectively mobile refrigeration systems, are commonly used to transport perishable cargo, such as, for example, meat, poultry, dairy products, cut flowers, and other fresh or frozen products, by road, rail, sea, or intermodally. In the case of refrigerated trucks, a transport refrigeration system is mounted to the truck, typically behind the tractor cabin or on the roof of the tractor cabin for maintaining a controlled temperature environment within the cargo box of the truck. In the case of refrigerated trailers, which are typically pulled behind a tractor cabin, a transport refrigeration system is mounted to the trailer, typically to the front wall of the trailer for maintaining a controller temperature environment within the cargo box of the trailer.
Conventionally, transport refrigeration systems used in connection with refrigerated trucks and refrigerated trailers include a transport refrigeration unit having a refrigerant compressor, a condenser with one or more associated condenser fans, an expansion device, and an evaporator, with one or more associated evaporator fans, which are connected via appropriate refrigerant lines in a closed refrigerant flow circuit. Air is drawn from the interior volume of the cargo box by means of the evaporator fan(s) associated with the evaporator, passed through the airside of the evaporator in heat exchange relationship with refrigerant whereby the refrigerant absorbs heat from the air, thereby cooling the air. The cooled air is then supplied back to the cargo box.
During movement of the transport refrigeration system, particularly tractor-trailer systems, air from the tractor cabin engine cooling system is expelled adjacent, such as below, the condenser air inlet of the transport refrigeration unit. The condenser draws in a mixture of ambient air and air from the tractor cabin engine cooling system and uses that to cool the refrigerant flowing there through. The increased temperature of the condenser air intake reduces the efficiency of the condenser and therefore the transport refrigeration unit. In addition, dust and dirt is also drawn through the condenser air intake causing deterioration of the efficiency and reliability of the transport refrigeration unit.